Crushing, Screening & Conveying

Crushing, Screening & Conveying

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Coal crushing and processing by Rotary breaker (4 replies)

(unknown)
8 years ago
(unknown) 8 years ago

What is the optimum value of ash that be reduced by comminution operation using rotary breaker in coal preparation? What modifications can be follow through to improve its ash reduction ability? I aim to enhance to separation of hard rocks and crushed coal via rotary breaker. The rotary breaker using has apertures of size 72mm and sufficient length and diameter to facilitate and separate rejects and product coal. But some of the smaller size hard rocks after breakage, also mix up with the product coal and increases the ash value of the product. I wish to reduce this amount. I needed some suggestions on what methodology can I implement to overcome the problem.

(unknown)
8 years ago
(unknown) 8 years ago
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Purpose of a breaker is to reduce the size of the run of mine coal and to reject some large hard rocks. The amount of rock rejected is a function of the non-selectivity of the mining operation and their size in relation to the breaker openings. The optimum would be all, but that would cause the reject of some coal, so the operation is such to just not reject coal (hopefully).

(unknown)
8 years ago
(unknown) 8 years ago
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I think you are trying to co relate the comminution, separation efficiency and product optimisation of Coal in rotary breaker operation. Trust its comminution not communication as written in the subject. Rotary breaker is designed to address the functionality of breaking the coal pieces and separate the hard unbreakable rocks with limitation.

To optimise the ash content you need to ascertain the population elemental analyses like ash, volatile material and raw coal in each size fraction and select the suitable process to materialize the desired one. It starts with rotary breaker in CHP and ends with floatation in coal washing through baths, DMS Cyclones, spirals. I mean we can optimise the smaller particle coal distribution in flotation, larger coal pieces distribution in rotary breaker effectively. One needs to understand population, particle sizes distribution, properties, liberation and then can contribute to separation effectively and easily.

Jean Rasczak
8 years ago
Jean Rasczak 8 years ago
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Rotary breaker is meant for only reduction in particle size. It totally depends on the liberation characteristics of coal. By size wise analysis of ash, VM and other properties you can find out the optimum size for liberation. If sufficient liberation occur at a particular size, automatically optimum reduction in ash will be achieved.

Zander Barcalow
8 years ago
Zander Barcalow 8 years ago
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The only way to do this would be to reduce the size of the openings until you are just starting to reject coal. But even then you will not remove all the rock. Is there any processing after the breaker? The normal method for such a situation would be to use a jig.

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